When products are designed and developed, files related to outcomes, such as specification documents, design documents, verification data, or the like, that are created at each of the designing and development steps, i.e., processing steps, are managed. These files are managed by, for example, a control system or an embedded system that is used in the automobile industry, the electronic manufacturing industry, the precision machinery industry, or the like in the course of products being manufactured. In this way, when the files are managed, files related to each other are associated in order to specify the affected region if a part of the specification or design needs to be changed. This associating process is used in order to improve traceability.
Patent Document 1: Japanese Laid-open Patent Publication No. 06-195255
However, with the file management described above, there is a problem in that files that have weak relationship are erroneously associated with each other. In this way, when files are erroneously associated, the affected region due to the change is not appropriately specified, and thus traceability is reduced.